1. Field of the Invention
This invention relates to a dideoxyneamine useful as an antimicrobial agent and a process for preparing the same. More particularly, this invention relates to 5,6-dideoxyneamine represented by the formula (I): ##STR1## and a process for preparing 5,6-dideoxyneamine which comprises hydrogenating a compound represented by the formula (II): ##STR2## wherein R.sup.1 represents a protective group for an amino group and R.sup.2 represents a protective group for a hydroxyl group, and then removing the protective groups for the amino and hydroxyl groups.
2. DESCRIPTION OF THE PRIOR ART
Extensive investigations have been conducted on syntheses of antibiotics effective against antibiotic-resistant microorganisms, particularly aminocyclitol derivatives.
3',4'-Dideoxyneamine which is a 3',4'-deoxy form of neamine has hitherto been proposed, and it has been confirmed that the 3',4'-dideoxyneamine is effective against various antibiotic-resistant microorganisms as reported in J. Antibiotics, 24 (10), 711 (1971).
Previously, 5-deoxyneamine or 6-deoxyneamine, which is a 5- or 6-deoxy form of a deoxystreptamine moiety of neamine, was developed (as described in Japanese Patent Application No. 137,222/75 (corresponding to U.S. Patent application Ser. No. 730,396, filed Oct. 7, 1976) now U.S. Pat. No. 4,103,082) with the expectation that such a deoxy form would exhibit antimicrobial activities on antibiotic-resistant microorganisms similar to those obtained with the above described 3',4'-dideoxyneamine.
Further investigations have now been made on 5,6-dideoxyneamine and processes for preparing the same with the expectation that such a 5,6-dideoxy form would have an increased effect against antibiotic-resistant microorganisms. As a result, it has now been found that the 5,6-dideoxyneamine has unexpectedly high activity against various antibiotic-resistant microorganisms, thus accomplishing the present invention.